The present invention relates to printing presses.
In printing presses, a common device of delivering the cut and folded product, such as a signature or book, at the end of the press is through the use of a delivery fly. This delivery fly is also commonly known as a fan, a fly fan, or bucket arrangement. The fly usually comprises several wheels driven on a common shaft, with the fly having pockets formed by fingers arranged around the wheel. The cut and folded products are deposited or inserted into the pockets one at a time, and, in turn, the products are stripped or removed from the fly onto a slow moving delivery belt transport in an overlapping or shingled fashion. Hence, the purpose of the fly is to take high speed products, slow them down, and deposit them onto the delivery belt for further processing.
It is a common occurrence for product jams to take place in the area of the fly, either at the entrance point or exit point. The jams occur for a variety of reasons, and may be caused by events that happen significantly in advance of reaching the fly area. Since the fly area is the point where the major speed change is imparted to the products, it becomes a spot where the jams are most likely to result.
These jams may or may not cause damage to the press, but, in any event, the jam is likely to be a problem to clear out in order that the press can be restarted. Clearing the jam is difficult because of the restricted space involved, and the longer it takes to get the press restarted the less productive the press becomes.